* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
      font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
    }
    
    body {
      display: flex;
      justify-content: center;
      align-items: center;
      min-height: 100vh;
      background: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
      padding: 20px;
    }
    
    .container {
      width: 100%;
      max-width: 500px;
    }
    
    .card {
      background: white;
      border-radius: 16px;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
      overflow: hidden;
      transition: all 0.3s ease;
    }
    
    .card-header {
      background: linear-gradient(135deg, #4776E6 0%, #8E54E9 100%);
      color: white;
      padding: 24px 30px;
      text-align: center;
    }
    
    .card-header h1 {
      font-size: 24px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    
    .card-header p {
      opacity: 0.9;
      font-size: 14px;
    }
    
    .card-body {
      padding: 30px;
    }
    
    .mode-switch {
      display: flex;
      justify-content: center;
      margin-bottom: 20px;
    }
    
    .btn-mode {
      padding: 10px 20px;
      border: none;
      background: none;
      font-size: 16px;
      font-weight: 600;
      cursor: pointer;
      color: #666;
      transition: all 0.3s ease;
    }
    
    .btn-mode.active {
      color: #4776E6;
      border-bottom: 2px solid #4776E6;
    }
    
    .status-indicator {
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      padding: 10px;
      border-radius: 50px;
      font-size: 14px;
      font-weight: 500;
    }
    
    .status-online {
      background: rgba(76, 175, 80, 0.1);
      color: #4CAF50;
    }
    
    .status-offline {
      background: rgba(244, 67, 54, 0.1);
      color: #F44336;
    }
    
    .status-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      margin-right: 8px;
    }
    
    .dot-online {
      background: #4CAF50;
    }
    
    .dot-offline {
      background: #F44336;
    }
    
    .loading-container {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      margin: 20px 0;
    }
    
    .loading-spinner {
      width: 40px;
      height: 40px;
      border: 4px solid #f3f3f3;
      border-top: 4px solid #4776E6;
      border-radius: 50%;
      animation: spin 1s linear infinite;
    }
    
    @keyframes spin {
      0% { transform: rotate(0deg); }
      100% { transform: rotate(360deg); }
    }
    
    .loading-text {
      margin-top: 10px;
      color: #666;
    }
    
    .user-info {
      display: flex;
      flex-direction: column;
      align-items: center;
      margin-bottom: 30px;
    }
    
    .avatar {
      width: 80px;
      height: 80px;
      border-radius: 50%;
      background: linear-gradient(135deg, #4776E6 0%, #8E54E9 100%);
      display: flex;
      justify-content: center;
      align-items: center;
      color: white;
      font-size: 32px;
      margin-bottom: 16px;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    }
    
    .user-name {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    
    .user-email {
      color: #666;
      font-size: 14px;
    }
    
    .login-form,
    .register-form {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    
    .form-group {
      display: flex;
      flex-direction: column;
    }
    
    .form-label {
      font-size: 14px;
      margin-bottom: 8px;
      color: #555;
      font-weight: 500;
    }
    
    .form-input {
      padding: 12px 16px;
      border: 1px solid #ddd;
      border-radius: 8px;
      font-size: 16px;
      transition: all 0.3s ease;
    }
    
    .form-input:focus {
      border-color: #4776E6;
      box-shadow: 0 0 0 2px rgba(71, 118, 230, 0.2);
      outline: none;
    }
    
    .error-message {
      color: #F44336;
      font-size: 12px;
      margin-top: 4px;
    }
    
    .password-strength {
      margin-top: 8px;
    }
    
    .strength-text {
      font-size: 12px;
      padding: 4px 8px;
      border-radius: 4px;
      display: inline-block;
    }
    
    .weak {
      background-color: #FFCDD2;
      color: #C62828;
    }
    
    .medium {
      background-color: #FFF9C4;
      color: #F57F17;
    }
    
    .strong {
      background-color: #C8E6C9;
      color: #388E3C;
    }
    
    .btn {
      display: inline-block;
      padding: 12px 24px;
      border-radius: 50px;
      font-weight: 600;
      text-align: center;
      cursor: pointer;
      transition: all 0.3s ease;
      border: none;
      font-size: 16px;
      width: 100%;
    }
    
    .btn-login {
      background: linear-gradient(135deg, #4776E6 0%, #8E54E9 100%);
      color: white;
      box-shadow: 0 4px 15px rgba(71, 118, 230, 0.3);
    }
    
    .btn-register {
      background: linear-gradient(135deg, #4CAF50 0%, #8BC34A 100%);
      color: white;
      box-shadow: 0 4px 15px rgba(76, 175, 80, 0.3);
    }
    
    .btn-logout {
      background: #f5f5f5;
      color: #666;
      border: 1px solid #ddd;
    }
    
    .btn:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
    }
    
    .btn:active {
      transform: translateY(0);
    }
    
    .btn:disabled {
      opacity: 0.6;
      cursor: not-allowed;
    }